Surgery supporting device and surgery supporting method

Abstract

This surgery supporting device comprises: an angiographic image acquisition unit that acquires a first angiographic image captured by an FPD disposed at a first position, and a second angiographic image captured by an FPD disposed at a second position; a line segment information acquisition unit that acquires first line segment information indicating a first line segment specified as the position and shape of a target blood vessel in the first angiographic image, and second line segment information indicating a second line segment specified as the position and shape of a target blood vessel in the second angiographic image; and a blood vessel information acquisition unit that acquires blood vessel information by using a first intersection point and a second intersection point obtained by projecting the same position in the target blood vessel, and does not use, for acquisition of blood vessel information, a first intersection point in which a second intersection point obtained by projecting the same position is not present, and the second intersection point in which the first intersection point obtained by projecting the same position is not present, the first intersection point being an intersection point between the first line segment and a parallel line parallel to an intersection line between a virtual plane and a first plane, and the second intersection point being an intersection point between the second line segment and a parallel line parallel to an intersection line between the virtual plane and a second plane.

Description

Surgery support device and surgery support method

[0001] The present disclosure relates to a surgery assistance device and a surgery assistance method.

[0002] In some cases, such as chronic total occlusion (CTO), blood vessels may become blocked by an obstruction. In such cases, the obstruction is removed or a stent is placed laterally to reopen the blood vessel. In such procedures, it is important for the surgeon to accurately grasp the position and shape of the blood vessel to be treated, from the viewpoints of improving the accuracy of the procedure, shortening the time required for the procedure, and reducing the burden on the patient. Patent Document 1 discloses a method for obtaining a two-dimensional image of a blood vessel by injecting a radiopaque contrast medium (contrast agent).

[0003] Patent No. 5886219

[0004] However, the technology disclosed in Patent Document 1 has a problem in that the position and shape of blood vessels can be confirmed only while the contrast agent is circulating, and injecting the contrast agent multiple times to confirm the position and shape of blood vessels increases the burden on the patient, which is undesirable. For this reason, there has been a demand for the development of a technology that can accurately obtain the position and shape of blood vessels to be treated while reducing the number of injections of the contrast agent.

[0005] The present disclosure has been made to solve at least part of the above-mentioned problems, and aims to provide a technology that can accurately obtain the position and shape of blood vessels to be treated while reducing the number of injections of contrast agent.

[0006] The present disclosure has been made to solve at least part of the above-mentioned problems, and can be realized in the following aspects.

[0007] (1) According to one aspect of the present disclosure, there is provided a surgery assistance device, the surgery assistance device including an angio-image acquisition unit that acquires a first angio-image including a target blood vessel imaged by an FPD disposed at a first position in a three-dimensional space where the target blood vessel exists and a second angio-image including the target blood vessel imaged by the FPD disposed at a second position different from the first position, first line segment information indicating a first line segment that is a line segment identified as the position and shape of the target blood vessel in a first plane that is a plane in the three-dimensional space indicated by the first angio-image, and second line segment information indicating a second line segment that is a line segment identified as the position and shape of the target blood vessel in a second plane that is a plane in the three-dimensional space indicated by the second angio-image. and a vascular information acquisition unit that acquires vascular information indicating the position and shape of the target blood vessel in the three-dimensional space using the first intersection and the second intersection, which are projected from the same position of the target blood vessel in the three-dimensional space, when the first intersection is the intersection of the first line segment with a parallel line parallel to the intersection line between the virtual plane and the first plane set in the three-dimensional space, and the second intersection is the intersection of the second line segment with a parallel line parallel to the intersection line between the virtual plane and the second plane, and does not use the first intersection, where the second intersection is not projected from the same position, or the second intersection, where the first intersection is not projected from the same position, in acquiring the vascular information.

[0008] According to this configuration, vascular information indicating the position and shape of a target blood vessel in three-dimensional space can be acquired using the first angio image and the second angio image. Therefore, the position and shape of the target blood vessel in three-dimensional space can be grasped without injecting additional contrast agent after injecting contrast agent to acquire the first angio image and the second angio image. According to this configuration, vascular information is acquired using the first and second intersections projected onto the same position of the target blood vessel in three-dimensional space, and first intersections where the second intersection projected onto the same position does not exist and second intersections where the first intersection projected onto the same position does not exist are not used to acquire vascular information. In other words, since vascular information is acquired using only the first and second intersections projected onto the same position, vascular information can be acquired with high accuracy. Therefore, according to this configuration, the position and shape of the blood vessel to be treated can be acquired with high accuracy while reducing the number of injections of contrast agent.

[0009] (2) The surgery assistance device of the above aspect may further include a vascular image generation unit that uses the vascular information to generate a vascular image representing the target blood vessel as viewed from the first position or the second position, and a composite image generation unit that generates a composite image in which the first angio-image or the second angio-image and the vascular image are superimposed. This configuration allows a vascular image representing the target blood vessel as viewed from the first position or the second position to be generated using vascular information accurately acquired by the vascular information acquisition unit. That is, after acquisition of the vascular information, a vascular image can be generated even if a contrast agent has not been injected into the target blood vessel. This configuration allows a composite image in which the first angio-image or the second angio-image and the vascular image are superimposed. Therefore, when a medical device is captured in the first angio-image or the second angio-image, the surgeon can proceed with the procedure while understanding the positional relationship between the medical device and the target blood vessel and the position and shape of the target blood vessel by viewing the composite image. This results in improved accuracy of the procedure, a shorter procedure time, and a reduced burden on the patient.

[0010] (3) In the surgery assistance device of the above aspect, the angio-image acquisition unit may further acquire a third angio-image captured by the FPD located at a third position different from the first position and the second position. When the vascular image generation unit acquires the third angio-image after acquiring the vascular information, the vascular image generation unit may use the vascular information to generate a different-viewpoint vascular image representing the target blood vessel as seen from the third position. The composite image generation unit may generate a different-viewpoint composite image in which the third angio-image and the different-viewpoint vascular image are superimposed. With this configuration, after acquiring the vascular information, it is possible to generate a different-start-point composite image in which a different-start-point vascular image representing the target blood vessel as seen from the third position is superimposed on the third angio-image captured from the third position different from the first and second positions without injecting a contrast agent. Therefore, by checking the different-start-point composite image in addition to the composite image, the surgeon can proceed with the procedure while understanding the positional relationship between the medical device and the target blood vessel and the position and shape of the target blood vessel. As a result, it is possible to further improve the accuracy of the procedure, shorten the time required for the procedure, and reduce the burden on the patient.

[0011] (4) In the surgery assistance device of the above aspect, the virtual plane may be a plane having a normal vector that is the cross product of a first view vector indicating the imaging direction of the FPD when the first angio-image is captured and a second view vector indicating the imaging direction of the FPD when the second angio-image is captured. With this configuration, a plane having a normal vector that is the cross product of the first view vector and the second view vector is set as the virtual plane, and vascular information can be acquired using the first intersection point and the second intersection point identified by the virtual plane.

[0012] The present disclosure has been made to solve at least part of the above-mentioned problems, and can be realized in the following forms: For example, the present disclosure can be realized in the form of an information processing device that acquires vascular information, an FPD (flat panel detector) that acquires vascular information, a system including these devices, a computer program that realizes the functions of these devices and systems, a server device for distributing the computer program, a non-transitory storage medium that stores the computer program, etc.

[0013] FIG. 1 is an explanatory diagram illustrating an example of the configuration of a surgery assistance system. FIG. 2 is an explanatory diagram illustrating LAO. FIG. 3 is an explanatory diagram illustrating RAO. FIG. 4 is an explanatory diagram illustrating CRA. FIG. 5 is an explanatory diagram illustrating CAU. FIG. 6 is a flowchart showing an example of a composite image generation process. FIG. 7 is an explanatory diagram of an operation screen used in the composite image generation process. FIG. 8 is an explanatory diagram showing an example of a first angio image. FIG. 9 is an explanatory diagram showing an example of a second angio image. FIG. 10 is an explanatory diagram of an intersection line. FIG. 11 is an explanatory diagram of a perpendicular line. FIG. 12 is an explanatory diagram of a first intersection point and a second intersection point. FIG. 13 is an explanatory diagram related to the acquisition of vascular information. FIG. 14 is an explanatory diagram related to the acquisition of vascular information. FIG. 15 is an explanatory diagram of a vascular image and a composite image. FIG. 16 is an explanatory diagram of a vascular image and a composite image.

[0014] First Embodiment FIG. 1 is an explanatory diagram illustrating the configuration of a surgery assistance system 1. The surgery assistance system 1 is a system for assisting in examinations and treatments. The surgery assistance system 1 includes a surgery assistance device 10, a vascular imaging device 20 having a flat panel detector (FPD), a display device 30, a table 40, and an operation unit 50. By including the surgery assistance device 10 (described later), the surgery assistance system 1 of this embodiment can generate a vascular image representing a target blood vessel corresponding to an image captured by an FPD (hereinafter referred to as an "angiogram"), and generate a composite image in which the angioimage and the vascular image are superimposed. The term "target blood vessel" refers to a blood vessel that is the target of either examination or treatment. However, the surgery assistance system 1 is not limited to the vascular system, and may also be used in biological lumens such as the lymphatic system, biliary system, urinary system, respiratory system, digestive system, secretory glands, and reproductive organs.

[0015] 1 illustrates mutually orthogonal X, Y, and Z axes. The X axis corresponds to the width direction of the blood vessel imaging device 20, the Y axis corresponds to the height direction of the blood vessel imaging device 20, and the Z axis corresponds to the depth direction of the blood vessel imaging device 20. The origin O of the three-dimensional coordinate system (XYZ coordinate system) consisting of the X, Y, and Z axes is set to the position of the heart 91 of the human body 90.

[0016] In a composite image generation process described below, the surgery support device 10 generates a vascular image representing a target blood vessel corresponding to an angioimage captured by an FPD, and generates a composite image in which the angioimage and the vascular image are superimposed. The surgery support device 10 includes a CPU, ROM, and RAM, and the CPU executes a computer program stored in the ROM to realize the functions of a main control unit 11, an angioimage acquisition unit 12, a line segment information acquisition unit 13, a vascular information acquisition unit 14, a vascular image generation unit 15, and a composite image generation unit 16. The surgery support device 10 is electrically connected to the control unit 29, display device 30, and operation unit 50 of the vascular imaging device 20.

[0017] The main controller 11 exchanges information with the controller 29 of the blood vessel imaging device 20, the display device 30, and the operation unit 50, and also controls the entire surgery assistance device 10. The main controller 11 controls the entire composite image generation process, which will be described later.

[0018] In the composite image generation process, the angio-image acquisition unit 12 acquires a first angio-image and a second angio-image from the blood vessel imaging device 20. A "first angio-image" is an angio-image including a target blood vessel imaged by an FPD placed at an arbitrary position in the three-dimensional space where the target blood vessel exists. The imaging position of the FPD when the first angio-image is acquired is also referred to as the "first position." A "second angio-image" is an angio-image including a target blood vessel imaged by an FPD placed at an arbitrary position different from the first position in the three-dimensional space where the target blood vessel exists. The imaging position of the FPD when the second angio-image is acquired is also referred to as the "second position."

[0019] In the composite image generation process, the line segment information acquisition unit 13 acquires first line segment information indicating a first line segment, which is a line segment identified as the position and shape of a target blood vessel on the first angio image, and second line segment information indicating a second line segment, which is a line segment identified as the position and shape of a target blood vessel on the second angio image. Details will be described later.

[0020] In the composite image generation process, the blood vessel information acquisition unit 14 acquires blood vessel information indicating the position and shape of the target blood vessel in three-dimensional space using the first line segment information, the second line segment information, etc. Details will be described later.

[0021] In the composite image generation process, the blood vessel image generation unit 15 generates a blood vessel image representing a target blood vessel corresponding to the first angio image or the second angio image captured by the FPD, as will be described in detail later.

[0022] In the composite image generation process, the composite image generation unit 16 generates a composite image in which the first angio image or the second angio image and the blood vessel image are superimposed and displayed. In this embodiment, the generated composite image is displayed on the display device 30. Details will be described later.

[0023] The blood vessel imaging device 20 has an FPD and is a device for obtaining an angioimage by converting X-rays that have passed through the human body into digital signals. The blood vessel imaging device 20 has a first FPD 21, a first X-ray tube assembly 22, a first C-arm 23, a first support unit 24, a second FPD 25, a second X-ray tube assembly 26, a second C-arm 27, a second support unit 28, and a control unit 29.

[0024] The first FPD 21 includes an X-ray flat panel detector, converts X-rays received from the first X-ray tube device 22 into electrical signals, and performs A / D (analog / digital) conversion to generate an angioimage. The first X-ray tube device 22 receives high voltage output from an X-ray high voltage device (not shown) and emits an X-ray beam. As indicated by the thick dashed line extending in the Y-axis direction in FIG. 1 , the X-ray beam emitted from the first X-ray tube device 22 passes through the human body 90 and enters the first FPD 21. The first C-arm 23 is a C-shaped arm (support) that fixes the first FPD 21 and the first X-ray tube device 22 in opposing positions. The first support 24 rotatably supports the first C-arm 23. That is, the first FPD 21 and the first X-ray tube assembly 22 can be moved to any imaging position around the human body 90 lying on the bed 41 while being fixed in opposing positions by the first C-arm 23. Hereinafter, the first FPD 21 and the first X-ray tube assembly 22 fixed to the first C-arm 23 will also be simply referred to as the "first FPD 21."

[0025] The second FPD 25 has a configuration similar to that of the first FPD 21. The second X-ray tube device 26 has a configuration similar to that of the first X-ray tube device 22. As indicated by the thick dashed line extending in the X-axis direction in FIG. 1 , the X-ray beam emitted from the second X-ray tube device 26 enters the second FPD 25 through the human body 90. The second C-arm 27 is a C-shaped arm (support) that fixes the second FPD 25 and the second X-ray tube device 26 in opposing positions. The second support unit 28 rotatably supports the second C-arm 27. That is, the second FPD 25 and the second X-ray tube device 26 can move to any imaging position around the human body 90 while being fixed in opposing positions by the second C-arm 27. Hereinafter, the second FPD 25 and the second X-ray tube device 26 fixed to the second C-arm 27 will also be simply referred to as the "second FPD 25."

[0026] Generally, the second FPD 25 is disposed in the normal direction of the first FPD 21. For example, as shown in Fig. 1 , when the first FPD 21 is positioned to image in the front direction of the human body 90 (the vertical direction of the human body 90, the longitudinal direction of the human body 90), the second FPD 25 is positioned to image in the horizontal direction of the human body 90 (the lateral direction of the human body 90). The blood vessel imaging device 20 may also be simply referred to as an "FPD" or an "FPD device."

[0027] The control unit 29 includes a CPU, ROM, and RAM, and the CPU executes a computer program stored in the ROM to control the entire angiography device 20. The control unit 29 is electrically connected to each of the first FPD 21, the second FPD 25, the first support unit 24, the second support unit 28, the display device 30, the table 40, and the operation unit 50. The control unit 29 displays angiographic images generated by the first FPD 21 and the second FPD 25 on the display device 30. In accordance with operation from the operation unit 50, the control unit 29 drives the first support unit 24 to rotate the first C-arm 23 and drives the second support unit 28 to rotate the second C-arm 27. Furthermore, in accordance with operation from the operation unit 50, the control unit 29 extends and retracts the extension unit 42 to change the height of the bed 41 and moves the table 40 in the Z-axis direction to change the position of the bed 41.

[0028] The display device 30 is connected to the surgery assistance device 10 and the control unit 29 of the blood vessel imaging device 20, and functions as an output interface for the surgery assistance device 10 and the blood vessel imaging device 20. The display device 30 has a monitor 31 and an arm 32. The monitor 31 is a "display unit" configured by well-known means such as a liquid crystal display, smart glasses, or a projector. The arm 32 supports and fixes the monitor 31.

[0029] The table 40 is a platform on which the human body 90 lies and is positioned near the first FPD 21 and the second FPD 25. The table 40 includes a bed 41, an extension / contraction unit 42, and legs 43. The bed 41 includes a mattress on which the human body 90 lies. The bed 41 is supported by the table 40 and is movable in the Z-axis direction. The extension / contraction unit 42 is configured to extend and contract in the Y-axis direction, thereby changing the height of the bed 41. The legs 43 support the bed 41 and the extension / contraction unit 42. As shown in FIG. 1 , the human body 90 lies face up on the bed 41 with its head 92 placed closer to the first FPD 21 and the second FPD 25 and its feet 93 placed farther from the first FPD 21 and the second FPD 25. This arrangement makes it easier for the first FPD 21 and the second FPD 25 to acquire images of the target blood vessels in the heart 91.

[0030] The operation unit 50 is connected to the surgery assistance device 10 and the control unit 29 of the vascular imaging device 20, and functions as an input interface for the surgery assistance device 10 and the vascular imaging device 20. The operation unit 50 is an "input unit" configured with well-known means such as a touch panel, operation buttons, operation levers, operation switches, a keyboard, a mouse, a voice input unit, a foot switch, etc. In the illustrated example, the operation unit 50 is fixed to the table 40.

[0031] FIGS. 2 to 5 are diagrams illustrating the imaging position of the first FPD 21. FIG. 2 is a diagram illustrating LAO, and FIG. 3 is a diagram illustrating RAO. As shown in FIG. 2, the case where the first FPD 21 is positioned on the left side of the human body 90 is called LAO (Left Anterior Oblique view). As shown in FIG. 3, the case where the first FPD 21 is positioned on the right side of the human body 90 is called RAO (Right Anterior Oblique view). FIG. 4 is a diagram illustrating CRA, and FIG. 5 is a diagram illustrating CAU. As shown in FIG. 4, the case where the first FPD 21 is positioned on the upper side of the human body 90 is called CRA (CRAnial). As shown in FIG. 5, the case where the first FPD 21 is positioned on the lower side of the human body 90 is called CAU (CAUdal). That is, the "imaging position of the first FPD 21" is specified by a combination of a left-right position (A1) and a top-bottom position (A2) as shown below. (A1) A tilt θ1 between either LAO or RAO and the Y axis passing through the center O of the human body 90, and (A2) A tilt θ2 between either CRA or CAU and the Y axis passing through the center O of the human body 90. The center O of the human body 90 is the position of the heart 91 of the human body 90. For example, "the imaging position of the first FPD 21 is (RAO28 CRA5)" means that the first FPD 21 is at a position of 28 degrees to the right of the human body 90 and at a position of 5 degrees above the human body 90.

[0032] 6 is a flowchart showing an example of composite image generation processing. The composite image generation processing can be started at any time, such as when the surgery assistance device 10 is powered on, when a predetermined application is started, or when the vascular imaging device 20 is started. In the following description, an example is given in which an angio image is obtained using the first FPD 21. However, angio images may also be obtained using the second FPD 25. In this case, the "first FPD 21" in the following description may be replaced with the "second FPD 25."

[0033] FIG. 7 is an explanatory diagram of an operation screen OS used in the composite image generation process. In this embodiment, the surgery support device 10 displays an operation screen OS as shown in FIG. 7 on the display device 30 and uses this operation screen OS to display instructions for various operations. The operation screen OS has an operation button display area A1 in which buttons for performing various operations are arranged, a canvas A2, and an instruction display area A3 in which various instruction messages are displayed. The canvas A2 is an area for displaying the first angioimage, the second angioimage, etc., which will be described later. The operation screen OS is merely an example, and various modifications are possible. For example, the instruction display area A3 of the operation screen OS may be omitted, and instructions may be executed by voice.

[0034] 8 is an explanatory diagram showing an example of a first angio image AG1 created through steps S1 to S5 of the composite image generation process. The first angio image AG1 shows the wire catheter CA and the guidewire GW, as well as a first line segment L1, which is a line segment identified as the position and shape of the target blood vessel TG. A lumen (not shown) for inserting the guidewire GW is formed inside the wire catheter CA. The first angio image AG1 shows the guidewire GW protruding from the distal end tp of the wire catheter CA. Details of the reference point RP indicated by the diagonal cross and the first line segment L1 will be described later.

[0035] Returning to the description of FIG. 6 . When the composite image generation process starts, in step S1, the surgery support device 10 instructs the surgeon via the operation screen OS to prepare for imaging by the first FPD 21. Specifically, preparing for imaging at this time means positioning the wire catheter CA with the guidewire GW inserted through its lumen near the target blood vessel TG of the human body 90 (see FIG. 1 ) lying on the bed 41, and then positioning the first FPD 21 at any position where the target blood vessel TG can be imaged. The surgeon prepares for imaging by the first FPD 21 according to the instructions. Because no contrast agent has been injected into the human body 90 during the imaging preparation, the canvas A2 displays an image captured by the first FPD 21, showing only the wire catheter CA with the guidewire GW inserted through its lumen. When the surgeon informs the surgery support device 10 via the operation screen OS that he or she has completed preparation for imaging, the surgery support device 10 executes step S2.

[0036] In step S2, the surgery support device 10 sets a reference point RP in the image of the wire catheter CA and the guidewire GW displayed on the canvas A2. In this embodiment, the position of the tip tp of the wire catheter CA is set as the reference point RP. The position of the tip tp may be identified by image recognition by the surgery support device 10, or the surgery support device 10 may instruct the surgeon to identify the position via the operation screen OS. Once the position of the tip tp is identified, a diagonal cross is added to that position to set the reference point RP (see FIG. 8 ), and then the surgery support device 10 executes step S3.

[0037] In step S3, the surgery support device 10 adjusts the imaging position of the first FPD 21 so that the reference point RP is positioned at the center of the canvas A2 in the image showing the wire catheter CA and the guidewire GW displayed on the canvas A2. The adjustment of the imaging position of the first FPD 21 may be performed by the surgery support device 10, or the surgery support device 10 may instruct the surgeon to do so via the operation screen OS. Once the imaging position has been adjusted, the surgery support device 10 executes step S4.

[0038] In step S4, the surgery support device 10 instructs the surgeon via the operation screen OS to capture a first angio image as a still image using the first FPD 21 after a contrast agent has been injected into the human body 90. Following the instruction, the surgeon captures the first angio image using the first FPD 21 after a contrast agent has been injected into the human body 90. The imaging position of the first FPD 21 at this time corresponds to the first position described above. The surgery support device 10 functions as the angio image acquisition unit 12 to acquire the first angio image captured as a still image. The first FPD 21 performs continuous imaging so that multiple first angio images are acquired by imaging using the first FPD 21. Each of the acquired first angio images includes the wire catheter CA and the guidewire GW, as well as target blood vessels TG with various shapes corresponding to the flow state of the contrast agent at each imaging timing. When the surgeon selects a first angioimage to be processed in step S5 from among these first angioimages, the surgery support device 10 executes step S5.

[0039] In step S5, the surgery support device 10 displays the first angio image selected by the surgeon on the canvas A2 and identifies a first line segment L1 (see FIG. 8 ) in the first angio image. The first line segment L1 is a line segment identified as the position and shape of the target blood vessel TG depicted in the first angio image. The first line segment L1 may be identified by the surgery support device 10 through image recognition, or may be identified by the surgeon himself / herself instructed to identify the first line segment L1 via the operation screen OS. When the first line segment L1 is identified, the surgery support device 10 functions as the line segment information acquisition unit 13 to acquire first line segment information indicating the first line segment L1 on the first angio image. The first line segment L1 identified in step S5 is drawn on the first angio image, thereby creating a first angio image AG1 as illustrated in FIG. 8 . That is, by executing the above-described steps S1 to S5, a first angio-image AG1 as shown in FIG. 8 is created and stored by the surgery support device 10.

[0040] 9 is an explanatory diagram showing an example of a second angio image AG2 created through steps S6 to S10 of the composite image generation process. As described above, the second angio image AG2 is an angio image including a target blood vessel imaged by an FPD placed at a second position, which is an arbitrary position different from the first position. The second angio image AG2 shows the wire catheter CA and guidewire GW, as in the first angio image AG1 shown in FIG. 8, and also shows a second line segment L2, which is a line segment identified as the position and shape of the target blood vessel TG. The second angio image AG2 corresponds to an angio image obtained by imaging the wire catheter CA, guidewire GW, and target blood vessel TG from a second position different from the first position while maintaining the three-dimensional positional relationship between the distal end tp and the target blood vessel TG when the imaging was performed in step S4.

[0041] Returning to the description of FIG. 6 , in step S6, the surgery support device 10 instructs the surgeon, via the operation screen OS, to prepare for imaging by the first FPD 21, as in step S1. Preparation for imaging at this time refers to placing the first FPD 21 at an arbitrary position where the target blood vessel TG can be imaged, while maintaining the three-dimensional positional relationship between the distal end tp and the target blood vessel TG when the imaging in step S4 is performed, and at a position (second position) different from the position (first position) of the first FPD 21 when the imaging in step S4 is performed. The surgeon places the first FPD 21 at the second position in accordance with the instructions. Because no contrast agent has been injected into the human body 90 during the preparation for imaging, the canvas A2 displays an image captured by the first FPD 21, showing only the wire catheter CA with the guidewire GW inserted through its lumen. When the surgeon informs the surgery support device 10 via the operation screen OS that he or she has completed preparation for imaging, the surgery support device 10 executes step S7.

[0042] In step S7, the surgery support device 10 sets a reference point RP in the image of the wire catheter CA and the guidewire GW displayed on the canvas A2, similar to step S2. Once the position of the tip tp is identified, the reference point RP is set by marking that position with a diagonal cross (see FIG. 9 ). The surgery support device 10 then executes step S8. The reference point RP set in step S7 and the reference point RP set on the first angio image AG1 (see FIG. 8 ) are considered to be points where the tip tp, existing in three-dimensional space, is projected onto each of the first angio image AG1 and the second angio image AG2. That is, the reference point RP set in step S7 and the reference point RP set on the first angio image AG1 (see FIG. 8 ) are considered to be points where the same position (tip tp) in three-dimensional space is projected onto each of the first angio image AG1 and the second angio image AG2.

[0043] In step S8, similar to step S3, the surgery support device 10 adjusts the imaging position of the first FPD 21 so that the reference point RP is positioned at the center of the canvas A2 in the image showing the wire catheter CA and the guidewire GW displayed on the canvas A2. After the imaging position is adjusted, the surgery support device 10 executes step S9.

[0044] In step S9, similar to step S4, the surgery support device 10 instructs the surgeon via the operation screen OS to capture a second angio image as a still image using the first FPD 21 after a contrast agent has been injected into the human body 90. Following the instruction, the surgeon captures the second angio image using the first FPD 21 after a contrast agent has been injected into the human body 90. The imaging position of the first FPD 21 at this time corresponds to the second position described above. The surgery support device 10 functions as the angio image acquisition unit 12 to acquire the second angio image captured as a still image. The first FPD 21 performs continuous imaging so that multiple second angio images are acquired by the imaging using the first FPD 21. Each of the acquired second angio images includes the wire catheter CA and the guidewire GW, as well as target blood vessels TG with various shapes corresponding to the flow state of the contrast agent at each imaging timing. When the surgeon selects a second angioimage to be processed in step S10 from among these second angioimages, the surgery support device 10 executes step S10.

[0045] In step S10, similar to step S5, the surgery support device 10 displays the second angio image selected by the surgeon on the canvas A2 and identifies a second line segment L2 (see FIG. 9 ) in the second angio image. The second line segment L2 is a line segment identified as the position and shape of the target blood vessel TG in the second angio image. When the second line segment L2 is identified, the surgery support device 10 functions as the line segment information acquisition unit 13 to acquire second line segment information indicating the second line segment L2 on the second angio image. The second line segment L2 identified in step S10 is drawn on the second angio image, thereby creating a second angio image AG2 as illustrated in FIG. 9 . That is, by executing steps S6 to S10 described above, the second angio image AG2 as illustrated in FIG. 9 is created and stored by the surgery support device 10. Once the second angio image AG2 is stored, the surgery support device 10 executes step S11.

[0046] FIG. 10 is an explanatory diagram of the intersection lines S1 and S2 calculated in step S11. The X, Y, and Z axes shown in FIG. 10 are the same as those shown in FIG. 1. The target blood vessel TG shown in FIG. 10 is a target blood vessel existing in three-dimensional space. The first view vector V1 is a vector representing the imaging direction of the first FPD 21 when the first angio image AG1 is captured. The second view vector V2 is a vector representing the imaging direction of the first FPD 21 when the second angio image AG2 is captured. The first plane F1 is a plane in three-dimensional space represented by the first angio image AG1. That is, the first angio image AG1 corresponds to the first plane F1 onto which the target blood vessel TG in a state in which a contrast agent is injected is projected. The first plane F1 is perpendicular to the first view vector V1. The second plane F2 is a plane in three-dimensional space represented by the second angio image AG2. That is, the second angio-image AG2 corresponds to the second plane F2 onto which the target blood vessel TG in a state in which a contrast agent has been injected is projected. The second plane F2 is also perpendicular to the second view vector V2. Fig. 10 shows a first line segment L1, which is a line segment identified as the shape of the target blood vessel TG in the first plane F1. Fig. 10 shows a second line segment L2, which is a line segment identified as the shape of the target blood vessel TG in the second plane F2. Although the wire catheter CA and guidewire GW are not shown in the three-dimensional space in Fig. 10, it is assumed that the wire catheter CA and guidewire GW are also projected onto the first plane F1 and the second plane F2 (the first angio-image AG1 and the second angio-image AG2).

[0047] The intersection line S1 is the intersection line between a virtual plane VP (described later) and a first plane F1. The intersection line S2 is the intersection line between the virtual plane VP and a second plane F2 (described later). An intersection line is a line indicating the position where two surfaces intersect. In this embodiment, the virtual plane VP is a plane whose normal vector BV (shown in FIG. 10 ) is the cross product of the first view vector V1 and the second view vector V2. In other words, the virtual plane VP is a plane parallel to the first view vector V1 and the second view vector V2 and perpendicular to the first plane F1 and the second plane F2. The first parallel line PL1 and the second parallel line PL2 shown in FIG. 10 will be described later.

[0048] The calculation of the normal vector BV, which is the premise for calculating the intersection lines S1 and S2, will be described. First, the positions (first position and second position) of the first FPD 21 when the first angio image and the second angio image, which are specified by the combination of either LAO or RAO and either CRA or CAU, are captured, are converted into polar coordinates using the following equation (1). In the following equation (1), RL val represents either the LAO or the RAO at the first position or the second position, respectively, and the numerical value CC val represents either CRA or CAU at the first and second positions, respectively.

[0049] Next, the polar coordinates indicating the first position and the second position calculated using equation (1) are converted into Cartesian coordinates using equation (2) shown below.

[0050] When the Cartesian coordinates indicating the first position calculated using equation (2) are (x1, y1, z1) and the Cartesian coordinates indicating the second position calculated using equation (2) are (x2, y2, z2), the normal vector BV(x B , y B , z B ) is expressed as the following equation (3).

[0051] FIG. 11 is an explanatory diagram of the perpendicular line Bs. The intersection lines S1 and S2 correspond to the perpendicular line Bs of the orthogonal projection vector Bp obtained by projecting the normal vector BV onto each of the first angio-image AG1 and the second angio-image AG2. The perpendicular line Bs is calculated in the following order. First, two vectors a1 (0, -z n , y n ), a2(y n , -x n Next, a plane passing through each of the vectors a1 and a2 is defined as a projection plane A (corresponding to the first plane F1 and the second plane F2), and a projection matrix P (projection matrix P onto the n-th plane Fn) of the n-th view vector Vn expressed by the following equation (4) is calculated. In the following equation (4), A T represents the transpose matrix of the projection plane A.

[0052] Next, the orthogonal projection vector Bp corresponding to the normal vector BV projected onto the projection plane A and the axial projection vector Zp corresponding to the z-axis (Ze(0,0,1)) projected onto the projection plane A are calculated using the following equations (5) and (6).

[0053] Next, the orthogonal projection vector Bp is expressed as a two-dimensional coordinate (x p , y p ) When the orthogonal projection vector Bp is clockwise (CW) as viewed from the axial projection vector Zp, the following formula (7) is used. When the orthogonal projection vector Bp is counterclockwise (CCW) as viewed from the axial projection vector Zp, the following formula (8) is used. The θ used in equations (7) and (8) can be calculated from the orthogonal projection vector Bp and the axial projection vector Zp. (x p , y p ) is treated as a unit vector.

[0054] Finally, the two-dimensional coordinates (x p , y p ) into the following equation (9), the perpendicular line Bs(x r , y r ) can be obtained. As mentioned above, the perpendicular line Bs(x r , y r ) corresponds to the intersection lines S1 and S2 (see FIG. 10).

[0055] In step S11, the surgery support device 10 functions as the vascular information acquisition unit 14 to set a virtual plane VP in three-dimensional space, calculate a normal vector BV using the above-mentioned formulas (1) to (3), and then calculate a perpendicular line Bs using the above-mentioned formulas (4) to (9), thereby calculating the intersection lines S1 and S2. After calculating the intersection lines S1 and S2, the surgery support device 10 executes step S12.

[0056] Fig. 12 is an explanatory diagram of the first intersection point N1 and the second intersection point N2 identified in step S12. The wire catheter CA and the guidewire GW are not shown in the first angio-image AG1 and the second angio-image AG2 shown in Fig. 12. The normal vector BV shown in Fig. 12 is the same as the normal vector BV shown in Fig. 10.

[0057] The first angio image AG1 shown in Figure 12 depicts first parallel lines PL1, which are multiple parallel lines parallel to the intersection line S1 (see Figure 10). The first parallel lines PL1 include a parallel line PR1 that passes through a reference point RP. The first parallel lines PL1 are arranged at equal intervals. In Figure 12, in addition to the parallel line PR1, first parallel lines PL1a-e are also shown as the first parallel lines PL1 arranged at equal intervals. A first intersection point N1 is the intersection point between the first parallel line PL1 and a first line segment L1.

[0058] The second angio-image AG2 shown in FIG. 12 depicts second parallel lines PL2, which are multiple parallel lines parallel to the intersection line S2 (see FIG. 10). The second parallel lines PL2 include a parallel line PR2 that passes through the reference point RP. The spacing between the second parallel lines PL2 is the same as the spacing between the first parallel lines PL1. In addition to the parallel line PR2, FIG. 12 also depicts second parallel lines PL2a-g as the equally spaced second parallel lines PL2. If the direction of the normal vector BV is taken as the height, the second parallel lines PL2a-e are positioned at the same height as the first parallel lines PL1a-e. The second intersection point N2 is the intersection point between the second parallel line PL2 and the second line segment L2.

[0059] The intersection lines S1 and S2 shown in Fig. 10 are the intersection lines between a virtual plane VP set at the position shown in Fig. 10 and the first and second planes F1 and F2. If the direction of the normal vector BV is taken as the height, they can also be considered as the first and second parallel lines PL1 and PL2, which are located at the same height. In Fig. 10, the first and second intersection points N1 and N2 between the intersection lines S1 and S2 (the first and second parallel lines PL1 and PL2) and the first and second line segments L1 and L2 are points where the position Ta of the target blood vessel TG in three-dimensional space is projected onto the first and second planes F1 and F2, respectively. Similarly, in Fig. 12, the first intersection points N1b-e of the first intersection point N1 and the second intersection points N2b-e of the second intersection points N2 are points where the same position of the target blood vessel TG in three-dimensional space is projected onto the first and second planes F1 and F2, respectively.

[0060] In step S12, the surgery support device 10, functioning as the vascular information acquisition unit 14, identifies the first intersection N1 and the second intersection N2 by drawing the first parallel line PL1 and the second parallel line PL2 based on the intersection line S1 and the intersection line S2 on the first angio image AG1 and the second angio image AG1, respectively. At this time, the surgery support device 10 classifies and stores the first intersection N1 and the second intersection N2 that project the same position of the target blood vessel TG in three-dimensional space (e.g., the first intersection N1b-e and the second intersection N2b-e in FIG. 12 ), the first intersection N1 that does not have the second intersection N2 that projects the same position (e.g., the first intersection N1a in FIG. 12 ), and the second intersection N2 that does not have the first intersection N1 that projects the same position (e.g., the second intersection N2f, N2g in FIG. 12 ). After identifying the first intersection N1 and the second intersection N2, the surgery assistance device 10 executes step S13.

[0061] In step S13, the surgery support device 10 functions as the vascular information acquisition unit 14 to acquire vascular information indicating the position and shape of the target blood vessel TG in three-dimensional space using a first intersection N1 and a second intersection N2 that project the same position of the target blood vessel TG in three-dimensional space. At this time, the surgery support device 10 does not use a first intersection N1 where a second intersection N2 projecting the same position does not exist or a second intersection N2 where a first intersection N1 projecting the same position does not exist, for acquiring vascular information. In the case of Figure 12, the first intersections N1b-e and the second intersections N2b-e are used for acquiring vascular information, but the first intersection N1a and the second intersections N2f and N2g are not used for acquiring vascular information. The vascular information includes the direction from the position of the reference point RP (the tip tp of the wire catheter CA) in three-dimensional space to each position of the target blood vessel TG, and the length from the position of the reference point RP to each position of the target blood vessel TG in three-dimensional space. In other words, the vascular information is information that indicates the position and shape of the target blood vessel TG in three-dimensional space relative to the reference point RP (the tip tp).

[0062] 13A and 13B are explanatory diagrams relating to the acquisition of vascular information. For ease of explanation, the first angio-image AG1 shown in Fig. 13A and the second angio-image AG2 shown in Fig. 13B are different from the first angio-image AG1 and the second angio-image AG2 shown in Fig. 12 in that the first parallel lines PL1 and the second parallel lines PL2 are omitted and position vectors P1b', P1c' and position vectors P2b', P2c' are added.

[0063] Position vectors P1b' and P1c' are vectors extending from reference point RP in the first angio image AG1 toward first intersection points N1b and N1c, respectively. Vectors extending from reference point RP in the first angio image AG1 toward each of the first intersection points N1 are collectively referred to as position vector P1'. Position vectors P2b' and P2c' are vectors extending from reference point RP in the second angio image AG2 toward second intersection points N2b and N2c, respectively. Vectors extending from reference point RP in the second angio image AG2 toward each of the second intersection points N2 are collectively referred to as position vector P2'. Hereinafter, the position vectors P1′ and P2′ that extend toward the first intersection point N1 and the second intersection point N2 projected from the same position of the target blood vessel TG in three-dimensional space are referred to as the corresponding position vectors P1′ and P2′. For example, the position vectors P1b′ and P2b′ are the corresponding position vectors P1′ and P2′.

[0064] The direction from the position of the reference point RP (the tip tp of the wire catheter CA) in three-dimensional space among the vascular information to each position of the target blood vessel TG can be calculated using the corresponding position vector P1 and the corresponding position vector P2. Specifically, a straight line is defined at the position where a plane defined by the corresponding position vector P1 and the first view vector V1 (see FIG. 10) intersects with a plane defined by the corresponding position vector P2 and the second view vector V2 (see FIG. 10), and the vector indicated by this straight line is calculated as the direction from the position of the reference point RP in three-dimensional space to each position of the target blood vessel TG. Details of the method for determining the direction of the vector indicated by the straight line at the position where two planes intersect are disclosed in International Application PCT / JP2021 / 034980.

[0065] FIG. 14 is an explanatory diagram regarding the acquisition of vascular information. Using FIG. 14 , calculation of the length from the position of the reference point RP in three-dimensional space to each position of the target blood vessel TG will be described. FIG. 14 shows a first view vector V1, a first angio image AG1, a reference point RP on the first angio image AG1, a reference point RP3 (described later), a position vector P1', a first intersection point N1, and a position vector P1 (described later). The reference point RP3 is the position of the reference point RP (tip tp) in three-dimensional space. As described above, the position vector P1' is a vector extending from the reference point RP in the first angio image AG1 toward each of the first intersection points N1. The position vector P1 is a vector extending from the position of the reference point RP (reference point RP3) in three-dimensional space to each position of the target blood vessel TG. The position vector P1' corresponds to the vector obtained by projecting the position vector P1 onto the first angio image AG1 (first plane F1). The length from the position of the reference point RP to each position of the target blood vessel TG in three-dimensional space corresponds to the length of the position vector P1. θ in Figure 14 is the angle between the first view vector V1 and the position vector P1.

[0066] If the first view vector V1 and the position vector P1 are unit vectors, θ can be calculated using the upper equation of the following equation (10), which is based on the formula for the dot product of vectors. The length of the position vector P1 can then be calculated using the lower equation of the following equation (10). In the upper equation of the following equation (10), "V1 x P1" represents the dot product of the first view vector V1 and the position vector P1. In the lower equation of the following equation (10), "P1" and "P1'" represent the length of the position vector P1 and the length of the position vector P1', respectively.

[0067] In step S13, the surgery assistance device 10 acquires vascular information using the method described with reference to Figures 13A, 13B, and 14. At this time, the surgery assistance device 10 stores the acquired vascular information. After acquiring the vascular information, the surgery assistance device 10 executes step S14.

[0068] 15A and 15B are explanatory diagrams of the vascular image BI and the composite image CP. In step S14, the surgery support device 10 functions as the vascular image generator 15 to generate a vascular image BI representing the target blood vessel TG viewed from the first position or the second position using vascular information. Then, the surgery support device 10 functions as the composite image generator 16 to generate a composite image CP in which the first angio image AG1 or the second angio image AG2 is superimposed on the vascular image BI. Specifically, the surgery support device 10 generates at least one of a composite image CP1 in which the vascular image BI1 representing the target blood vessel TG viewed from the first position is superimposed on the first angio image AG1, and a composite image CP2 in which the vascular image BI2 representing the target blood vessel TG viewed from the second position is superimposed on the second angio image AG2. The generated composite image CP is displayed on the display device 30. 15A and 15B show the vascular image BI, but do not show the shape of the target blood vessel TG or the first and second line segments L1 and L2 that were present in the first and second angio images AG1 and AG2 due to the flow of contrast medium. However, the shape of the target blood vessel TG or the first and second line segments L1 and L2 that were present in the first and second angio images AG1 and AG2 due to the flow of contrast medium may be shown in the composite images CP1 and CP2 at positions that overlap with the vascular images BI1 and BI2. After generating the composite image CP, the surgery support device 10 ends the composite image generation process shown in FIG.

[0069] After acquiring vascular information through the composite image generation process, the surgery support device 10 can superimpose a different-viewpoint vascular image representing the target blood vessel TG as viewed from the third position on a third angio image captured by an FPD placed at a third position different from the first and second positions. Therefore, the surgery support device 10, which also functions as the angio image acquisition unit 12, can acquire the third angio image in addition to the first and second angio images. The third angio image is preferably captured while maintaining the three-dimensional positional relationship between the distal end tp and the target blood vessel TG that was observed when the imaging was performed in steps S4 and S6 of the composite image generation process. Therefore, it is not necessary to capture the third angio image while a contrast agent is injected into the human body 90. The procedure is described below.

[0070] When the surgery support device 10 acquires the third angio image after acquiring the vascular information, the surgery support device 10 functions as the vascular image generator 15 to generate a different-viewpoint vascular image representing the target blood vessel as viewed from a third position using the vascular information. Specifically, the surgery support device 10 sets the position of the tip tp of the wire catheter CA shown in the third angio image as a reference point RP, and then calculates the position and shape of the target blood vessel TG as viewed from the third position by referring to the position of the reference point RP, the third position, and the vascular information, thereby generating a different-viewpoint vascular image to be displayed superimposed on the third angio image. The different-viewpoint vascular image corresponds to an image obtained by projecting the shape of the target blood vessel TG in three-dimensional space identified based on the vascular information onto a plane (corresponding to the first and second planes F1 and F2 in the first and second angio images) perpendicular to the direction of a third view vector indicating the imaging direction of the FPD when the third angio image was captured. The surgery support device 10 then functions as the composite image generator 16 to generate a different-viewpoint composite image in which the third angioimage and the different-viewpoint vascular image are superimposed and displayed. Because the different-viewpoint vascular image can be generated using vascular information acquired through the composite image generation process, the surgery support device 10 can generate the different-viewpoint composite image without newly injecting a contrast agent into the human body 90. The different-viewpoint composite image is not limited to a still image, but may be a moving image displayed in real time. In such a case, the surgeon can move the guidewire GW protruding from the distal end tp toward the target blood vessel TG (different-viewpoint vascular image) shown on the different-viewpoint composite image while viewing the different-viewpoint composite image while fixing the position of the distal end tp in three-dimensional space.

[0071] As described above, the surgery support device 10 included in the surgery support system 1 of the first embodiment can acquire vascular information indicating the position and shape of the target blood vessel TG in three-dimensional space using the first angio image AG1 and the second angio image AG2 (see FIGS. 8, 9, 12, and 13). Therefore, after the contrast agent is injected to acquire the first angio image AG1 and the second angio image AG2, the position and shape of the target blood vessel TG in three-dimensional space can be grasped without further contrast agent injection. The surgery support device 10 acquires vascular information using the first intersection N1 and the second intersection N2, which are projections of the same position of the target blood vessel TG in three-dimensional space. However, first intersections where no second intersections projecting the same position exist and second intersections where no first intersections projecting the same position exist are not used to acquire vascular information (see FIGS. 12 and 13). In other words, since the vascular information is acquired using only the first intersection point N1 and the second intersection point N2 that are projections of the same position, the vascular information can be acquired with high accuracy. Therefore, the surgery support device 10 can accurately acquire the position and shape of the blood vessel to be treated while reducing the number of injections of contrast agent.

[0072] The surgery support device 10 included in the surgery support system 1 of the first embodiment functions as a vascular image generator 15 and a composite image generator 16. Therefore, by functioning as the vascular information acquirer 14, the device can generate a vascular image BI representing the target blood vessel TG as viewed from a first position or a second position using vascular information acquired with high accuracy. That is, after acquiring the vascular information, the device can generate a vascular image BI even if a contrast agent has not been injected into the target blood vessel TG. The surgery support device 10 can generate a composite image CP in which the first angio image AG1 or the second angio image AG2 and the vascular image BI are superimposed (see FIGS. 15A and 15B ). Therefore, when a medical device (e.g., a wire catheter CA or a guidewire GW) is captured in the first angio image AG1 or the second angio image AG2, the surgeon can proceed with the procedure while understanding the positional relationship between the medical device and the target blood vessel TG and the position and shape of the target blood vessel TG by viewing the composite image CP. As a result, it is possible to improve the accuracy of the procedure, shorten the time required for the procedure, and reduce the burden on the patient.

[0073] The surgery support device 10 included in the surgery support system 1 of the first embodiment can generate a different-start-point composite image by superimposing a different-start-point vascular image representing the target blood vessel as viewed from a third position on a third angio image captured from a third position different from the first and second positions, without injecting a new contrast agent, once vascular information has been acquired. Therefore, by checking the different-start-point composite image in addition to the composite image CP, the surgeon can proceed with the procedure while understanding the positional relationship between the medical device and the target blood vessel TG, as well as the position and shape of the target blood vessel TG. This can further improve the accuracy of the procedure, shorten the time required for the procedure, and reduce the burden on the patient.

[0074] In the surgery support device 10 included in the surgery support system 1 of the first embodiment, a plane having a normal vector BV that is the cross product of a first view vector V1 and a second view vector V2 is set as a virtual plane VP, and vascular information can be acquired using a first intersection N1 and a second intersection N2 identified by the virtual plane VP. Of course, to acquire vascular information, the first intersection N1 and the second intersection N2 that are projected onto the same position of the target blood vessel TG in three-dimensional space are used, and the first intersection N1 where the second intersection N2 projected onto the same position does not exist and the second intersection N2 where the first intersection N1 projected onto the same position does not exist are not used to acquire vascular information.

[0075] <Modifications of the Present Embodiment> The present disclosure is not limited to the above-described embodiment, and can be implemented in various forms without departing from the spirit of the present disclosure. For example, part of the configuration realized by hardware may be replaced with software, and conversely, part of the configuration realized by software may be replaced with hardware. In addition, for example, the following modifications are also possible.

[0076] In the above embodiment, the configuration of the surgery assistance system 1 has been exemplified. However, the configuration of the surgery assistance system 1 can be modified in various ways. For example, the display device 30 may be a monitor or touch panel built into the surgery assistance device 10. For example, the vascular imaging device 20 may be configured to have a single FPD (in other words, a configuration without the second FPD 25). For example, the surgery assistance system 1 may include other medical devices (e.g., a CT device, an MRI device), etc., not shown.

[0077] The above embodiment has shown the configuration of the surgery assistance device 10. However, various modifications are possible to the configuration of the surgery assistance device 10. For example, the functions of each functional unit of the surgery assistance device 10 may be realized by cooperation between multiple devices connected via a network.

[0078] In the above embodiment, an example of the procedure for the composite image generation process is shown. However, the procedure for the composite image generation process described in Fig. 6 is merely an example, and various modifications are possible. For example, the order of execution of each step may be changed, at least some steps may be omitted, or other steps not described may be executed.

[0079] In the above embodiment, the first parallel lines PL1 and the second parallel lines PL2 are arranged at equal intervals. However, the above-described first parallel lines PL1 and second parallel lines PL2 are merely examples, and various modifications are possible. For example, the first parallel lines PL1 may be arranged at unequal intervals as long as there is a second parallel line PL2 that is arranged at the same height in the direction of the normal vector BV.

[0080] In the above embodiment, the vascular information includes the direction from the position of the reference point RP to each position of the target blood vessel TG in three-dimensional space and the length from the position of the reference point RP to each position of the target blood vessel TG in three-dimensional space. However, the above-described vascular information is merely an example, and various modifications are possible. For example, the vascular information may be defined by any information, such as a set of point sequence coordinates forming the outer edge of the target blood vessel or a set of coordinates of characteristic points on the outer edge of the target blood vessel.

[0081] In the above embodiment, the virtual plane VP is a plane whose normal vector BV is the cross product of the first view vector V1 and the second view vector V2. However, the above-described virtual plane VP is merely an example, and various modifications are possible. For example, the virtual plane VP may be any plane as long as it is not parallel to either the first plane F1 or the second plane F2. Even in such a case, the intersection lines S1 and S2 are calculated based on the virtual plane VP, and then the first and second parallel lines PL1 and PL2 are drawn to identify the first and second intersection points N1 and N2. The first and second intersection points N1 and N2 projected from the same positions of the target blood vessel TG in three-dimensional space can be used to acquire vascular information and generate a composite image.

[0082] In the above embodiment, the direction from the position of the reference point RP in three-dimensional space to each position of the target blood vessel TG was calculated using a method of defining a straight line at the position where two planes intersect. However, this method is merely an example, and various modifications are possible. For example, the direction from the position of the reference point RP in three-dimensional space to each position of the target blood vessel TG may be calculated by using Equations 1 to 18 disclosed in International Application No. PCT / JP2021 / 034980.

[0083] This aspect has been described above based on embodiments and modifications, but the above-described embodiments are intended to facilitate understanding of this aspect and are not intended to limit this aspect. This aspect may be modified or improved without departing from the spirit and scope of the claims, and equivalents thereof are included in this aspect. If a technical feature is not described as essential in this specification, it may be deleted as appropriate.

[0084] The functions performed by the components described herein may be implemented in circuitry or processing circuitry, including general-purpose processors, application-specific processors, integrated circuits, ASICs (Application Specific Integrated Circuits), CPUs (Central Processing Units), conventional circuits, and / or combinations thereof, programmed to perform the described functions. Processors include transistors and other circuits and are considered circuitry or processing circuitry. A processor may also be a programmed processor that executes a program stored in memory. In this specification, a circuit, unit, or means is hardware that is programmed to perform or executes the described functions. The hardware may be any hardware disclosed herein or any hardware known to be programmed to perform or execute the described functions. If the hardware is a processor, which is considered a type of circuitry, the circuit, means, or unit is a combination of hardware and software used to configure the hardware and / or processor.

Claims

1. A surgery support device (10), comprising: an angio-image acquisition unit (12) that acquires a first angio-image (AG1) including a target blood vessel (TG) imaged by an FPD (21, 25) placed at a first position in a three-dimensional space where the target blood vessel (TG) exists, and a second angio-image (AG2) including the target blood vessel (TG) imaged by the FPD (21, 25) placed at a second position different from the first position; a line segment information acquisition unit (13) that acquires first line segment information indicating a first line segment (L1), which is a line segment identified as the position and shape of the target blood vessel (TG) in a first plane (F1), which is a plane in the three-dimensional space indicated by the first angio-image (AG1), and second line segment information indicating a second line segment (L2), which is a line segment identified as the position and shape of the target blood vessel (TG) in a second plane (F2), which is a plane in the three-dimensional space indicated by the second angio-image (AG2); When the intersection of a parallel line (PL1) parallel to an intersection line (S1) between a virtual plane (VP) set in the three-dimensional space and the first plane (F1) and the first line segment (L1) is defined as a first intersection point (N1), and the intersection of a parallel line (PL2) parallel to an intersection line (S2) between the virtual plane (VP) and the second plane (F2) and the second line segment (L2) is defined as a second intersection point (N2), the same position of the target blood vessel (TG) projected on the three-dimensional space is defined as a first intersection point (N1). a vascular information acquisition unit (14) that acquires vascular information indicating the position and shape of the target blood vessel (TG) in the three-dimensional space using a first intersection (N1) and the second intersection (N2), and does not use the first intersection (N1) where the second intersection (N2) projecting the same position does not exist and the second intersection (N2) where the first intersection (N1) projecting the same position does not exist, in acquiring the vascular information.

2. A surgical support device (10) as described in claim 1, further comprising: a vascular image generation unit (15) that uses the vascular information to generate a vascular image (BI) representing the target blood vessel (TG) as viewed from the first position or the second position; and a composite image generation unit (16) that generates a composite image (CP) in which the first angio image (AG1) or the second angio image (AG2) and the vascular image (BI) are superimposed and displayed.

3. A surgical support device (10) as described in claim 2, wherein the angio-image acquisition unit (12) is further capable of acquiring a third angio-image captured by the FPD (21, 25) placed at a third position different from the first position and the second position, the vascular image generation unit (15), when acquiring the third angio-image after acquiring the vascular information, uses the vascular information to generate a different-viewpoint vascular image representing the target blood vessel (TG) as seen from the third position, and the composite image generation unit (16) generates a different-viewpoint composite image in which the third angio-image and the different-viewpoint vascular image are superimposed and displayed.

4. A surgical support device (10) according to any one of claims 1 to 3, wherein the virtual plane (VP) is a plane having a normal vector (BV) which is the cross product of a first view vector (V1) indicating the imaging direction of the FPD (21, 25) when the first angio image (AG1) is captured and a second view vector (V2) indicating the imaging direction of the FPD (21, 25) when the second angio image (AG2) is captured.

5. A surgical assistance method, comprising: acquiring a first angio-image (AG1) including a target blood vessel (TG) imaged by an FPD (21, 25) placed at a first position in a three-dimensional space where the target blood vessel (TG) exists; and acquiring a second angio-image (AG2) including the target blood vessel (TG) imaged by an FPD (21, 25) placed at a second position different from the first position; acquiring first line segment information indicating a first line segment (L1) that is a line segment identified as the position and shape of the target blood vessel (TG) on a first plane (F1) that is a plane in the three-dimensional space indicated by the first angio-image (AG1); and acquiring second line segment information indicating a second line segment (L2) that is a line segment identified as the position and shape of the target blood vessel (TG) on a second plane (F2) that is a plane in the three-dimensional space indicated by the second angio-image (AG2); a first intersection (N1) being the intersection of a parallel line (PL1) parallel to an intersection line (S1) between a virtual plane (VP) set in the three-dimensional space and the first plane (F1) and the first line segment (L1), and a second intersection (N2) being the intersection of a parallel line (PL2) parallel to an intersection line (S2) between the virtual plane (VP) and the second plane (F2) and the second line segment (L2), the first intersection (N1) and the second intersection (N2) being projected to the same position of the target blood vessel (TG) in the three-dimensional space are used to acquire vascular information indicating the position and shape of the target blood vessel (TG) in the three-dimensional space, and the first intersection (N1) where the second intersection (N2) where the first intersection (N1) where the same position is projected does not exist and the second intersection (N2) where the first intersection (N1) where the same position is projected does not exist are not used to acquire the vascular information.

6. A surgical support method according to claim 5, further comprising: using the vascular information to generate a vascular image (BI) representing the target blood vessel (TG) as viewed from the first position or the second position; and generating a composite image (CP) in which the first angio image (AG1) or the second angio image (AG2) and the vascular image (BI) are superimposed.

7. A surgical support method as described in claim 6, further comprising: when a third angio-image is acquired by the FPD (21, 25) placed at a third position different from the first position and the second position after acquiring the vascular information, generating a different viewpoint vascular image representing the target blood vessel (TG) as seen from the third position using the vascular information; and generating a different viewpoint composite image in which the third angio-image and the different viewpoint vascular image are superimposed and displayed.

8. A surgical assistance method according to any one of claims 5 to 7, wherein the virtual plane (VP) is a plane having a normal vector (BV) which is the cross product of a first view vector (V1) indicating the imaging direction of the FPD (21, 25) when the first angio image (AG1) is captured and a second view vector (V2) indicating the imaging direction of the FPD (21, 25) when the second angio image (AG2) is captured.

9. A surgery assistance device (10) comprising at least one processor and at least one memory containing computer program code, the at least one memory and the computer program code being configured to, in conjunction with the at least one processor, cause the surgery assistance device (10) to perform at least the following operations: acquire a first angio-image (AG1) including a target blood vessel (TG) imaged by an FPD (21, 25) placed at a first position in a three-dimensional space in which the target blood vessel (TG) is present, and a second angio-image (AG2) including the target blood vessel (TG) imaged by the FPD (21, 25) placed at a second position different from the first position; Obtain first line segment information indicating a first line segment (L1) which is a line segment identified as the position and shape of the target blood vessel (TG) in a first plane (F1) which is a plane in the three-dimensional space indicated by the first angio image (AG1), and second line segment information indicating a second line segment (L2) which is a line segment identified as the position and shape of the target blood vessel (TG) in a second plane (F2) which is a plane in the three-dimensional space indicated by the second angio image (AG2), a surgical assistance device (10) for acquiring vascular information indicating the position and shape of the target blood vessel (TG) in the three-dimensional space using the first intersection (N1) and the second intersection (N2) obtained by projecting the same position of the target blood vessel (TG) in the three-dimensional space, where the first intersection (N1) does not have the second intersection (N2) and the second intersection (N2) obtained by projecting the same position of the target blood vessel (TG) in the three-dimensional space, and where the first intersection (N1) does not have the second intersection (N2) obtained by projecting the same position, and where the second intersection (N2) does not have the first intersection (N1) and the first intersection (N2) obtained by projecting the same position, are not used to acquire the vascular information.

10. A surgical support device (10) as described in claim 9, further comprising: using the vascular information, generating a vascular image (BI) representing the target blood vessel (TG) as viewed from the first position or the second position; and generating a composite image (CP) in which the first angio image (AG1) or the second angio image (AG2) and the vascular image (BI) are superimposed.

11. A surgical support device (10) as described in claim 10, further comprising: when a third angio-image is acquired by the FPD (21, 25) placed at a third position different from the first position and the second position after acquiring the vascular information, the surgical support device (10) generates a different viewpoint vascular image representing the target blood vessel (TG) as seen from the third position using the vascular information; and generates a different viewpoint composite image in which the third angio-image and the different viewpoint vascular image are superimposed and displayed.

12. A surgical support device (10) according to any one of claims 9 to 11, wherein the virtual plane (VP) is a plane having a normal vector (BV) which is the cross product of a first view vector (V1) indicating the imaging direction of the FPD (21, 25) when the first angio image (AG1) is captured and a second view vector (V2) indicating the imaging direction of the FPD (21, 25) when the second angio image (AG2) is captured.

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